Discussion \n\n\n\tThe FAA learned of 13 IFSD events on certain IAE PW1100G-JM model turbofan engines beginning in October, 2018. After further analysis, IAE determined that the integrated drive generator (IDG) oil pump drive gearshaft assembly in the MGB assembly fractured during engine operation as a result of high-cycle fatigue. In response, IAE subsequently redesigned the IDG oil pump drive gearshaft assembly in the MGB assembly with an axially thicker gear web, a radially thicker gear rim, and an improved tooth tip relief to improve MGB assembly durability and reliability. IAE also redesigned the EEC software to restrict engine operation to certain parameters. This condition, if not addressed, could result in failure of one or more engines, loss of thrust control, and loss of the airplane. The FAA is issuing this AD to address the unsafe condition on these products. \n\nRelated Service Information \n\n\n\tThe FAA reviewed PW Service Bulletin (SB) PW1000G-C-72-00-0129-00A- 930A-D, Original Issue, dated April 18, 2019, and PW SB PW1000G-C-73- 00-0037-00A-930A-D, Original Issue, dated May 28, 2019. PW SB PW1000G- C-72-00-0129-00A-930A-D, Original Issue, dated April 18, 2019, describes procedures for replacing the IDG oil pump drive gearshaft assembly in the MGB assembly. PW SB PW1000G-C-73-00-0037-00A-930A-D, Original Issue, dated May 28, 2019, describes procedures for replacing the EEC software to incorporate FCS 5.0 software. \n\nFAA's Determination \n\n\n\tThe FAA is issuing this AD because it evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design. \n\nAD Requirements \n\n\n\tThis AD requires the removal of the MGB assembly and EEC software and the installation parts and software versions eligible for installation. \n\nInterim Action \n\n\n\tThese actions are interim actions, and the FAA may do additional rulemaking in the future for removal and replacement of the MGB assembly on the engines that do not operate on 180-minute or 120-minute extended operations (ETOPS) flights. \n\nFAA's Justification and Determination of the Effective Date \n\n\n\tAn unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule. Multiple IAE PW1100G-JM model turbofan engines experienced MGB assembly failures recently, which resulted in IFSDs. The MGB assemblies must be removed for ETOPS operators within 90 or 120 days after the effective date of this AD, depending on the length of the operator's ETOPS flights, to ensure the MGB assemblies are replaced before fractures develop that could result in the failure of both MGB assemblies and a dual IFSD event. Therefore, the FAA finds good cause that notice and opportunity for priorpublic comment are impracticable. In addition, for the reason stated above, the FAA finds that good cause exists for making this amendment effective in less than 30 days. \n\nComments Invited \n\n\n\tThis AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment. However, the FAA invites you to send any written data, views, or arguments about this final rule. Send your \n\n((Page 27512)) \n\ncomments to an address listed under the ADDRESSES section. Include the docket number FAA-2019-0393 and Product Identifier 2019-NE-14-AD at the beginning of your comments. The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of this final rule. The FAA will consider all comments received by the closing date and may amend this final rule because of those comments. \n\tThe FAA will post all comments received, without change, to http://www.regulations.gov, including any personal information you provide. The FAA will also post a report summarizing each substantive verbal contact received about this final rule. \n\nRegulatory Flexibility Act \n\n\n\tThe requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without notice and comment, RFA analysis is not required. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects 72 engines installed on airplanes of U.S. registry. \n\tThe FAA estimates the following costs to comply with this AD: \n\n\n\tEstimated Costs ---------------------------------------------------------------------------------------------------------------- \n\tCost per Cost on U.S. \n\tAction Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Replace the MGB assembly.............. 13 work-hours x $85 per $75,000 $76,105 $5,479,560 \n\thour = $1,105. Replace the EEC software.............. 3 work-hours x $85 per 0 255 18,360 \n\thour = $255. ---------------------------------------------------------------------------------------------------------------- \n\nAuthority for This Rulemaking \n\n\n\tTitle 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. ''Subtitle VII: Aviation Programs'' describes in more detail the scope of the Agency's authority. \n\tThe FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: ''General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. \n\tThis AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to engines, propellers, and associated appliances to the Manager, Engine and Propeller Standards Branch, Policy and Innovation Division. \n\nRegulatory Findings \n\n\n\tThis AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, and \n\t(2) Will not affect intrastate aviation in Alaska. \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.